Hi mate,
Key thing is you have a nice space to achieve 'something'. I think if you eliminated everything in the middle of the right hand side including the station and turntable, you would really have something to work with. You'd now have a lovely single-track run, with huge potential for scenics and making it look like somewhere in the UK in Era 2 (i.e. I'm guessing you are aiming for Edwardian feel). The bottom right part of the loop could be a through station and passing point for trains, then more realistic might be a goods yard/cattle dock in the middle. Many starters wish for too much, but with your single track roundy, you could really excel. On left hand edge, you could put in 3 siding loops for stabling and assembling trains, all hidden in a scenic break with tunnel entrances top and bottom left.
Next you need to decide where your single-track line might be, because this will govern the rolling stock you need, the housing styles, even the fences!! What is your preferred Railway Company to work with ? Is it a LBSCR branch line in Sussex (Bluebell, Sussex-Surrey border e.g. Christ's hospital to Guildford)? Is it a GWR branch? Is it GER in East Anglia (Suffolk/Norfolk/borders etc) ? Is it LNWR, Midland, GNR.?? There are some really nice locos out there these days, for any of these and other companies. You can really do something nice.
Actually on your layout you would not even need a turntable because it would be highly likely that you only need tank locos.
Just some initial thoughts, happy to help with other details, between us on this forum the is a lot of historical expertise.
Cheers
6991
PS Of course, if you want to spend money on whatever you want and run whatever, that is your prerogative, we all know that. I just see a really nice opportunity to create a good pre-WW1 layout here.